Merrill watched Wednesday’s practice at Yost Ice Arena with his neck immobilized in a brace. Berenson said Merrill will be immobilized for several weeks, but expects him to return to action this season.

The announcement comes a day before the Wolverines open their season at home against Rochester Institute of Technology Thursday.

Merrill’s injury is a significant blow for a Michigan defensive group considered to be one of the top in the CCHA coming into the season. The Brighton native put up 25 points two seasons ago, fourth-most by a freshman in team history, and had 11 points in 19 games last year in a suspension-shortened season.

Merrill suffered the injury during the second period of Michigan’s 7-3 win over Windsor, when he took a hard hit into the end boards. Berenson said the hit was clean, but forced Merrill awkwardly into the boards.

Berenson said an MRI and CAT scan revealed the fracture.

The injury is the latest turn in what’s been an eventful Michigan career for Merrill. After his standout freshman season, Merrill was suspended for the first 24 games of last season for a violation of team rules.

Over the summer, he contemplated turning professional before opting to return to Michigan. Berenson talked in the preseason about the increased level of maturity he’d seen in Merrill this year.

“It’s too bad, it’s tough, but Jonny’s got a good attitude and he’ll handle it,” Berenson said. “He’ll come back and be better than ever.”

“I think it’s an opportunity for Kevin Clare to play with Trouba in that role that Jonny played, just defensively and (penalty kill),” Berenson said. “Kevin Clare’s been an improving player since day one.”

Michigan’s other defensive pairings in Thursday’s opener will be Brennan Serville-Lee Moffie and Mac Bennett-Mike Chiasson.